The present invention generally relates to a stretch resistant plantar fascia support system. More particularly, the present invention relates to a stretch resistant plantar fascia support system that may be adhesively applied to a foot to provide relief from plantar fasciitis.
FIG. 1 is a dissected bottom view of a human foot 100 provided to illustrate some of the parts of a plantar fascia 110 located in the bottom of the human foot 100. As shown in FIG. 1, the plantar fascia 110 extends from about the location of the heel 101 to about the location of the ball 102 of the foot. The plantar fascia 110 includes medial plantar fascia 120, superficial tracts 130, a central component of the plantar fascia 140, and a lateral component of the plantar fascia 150. The separate portions of the plantar fascia 110 act as a shock absorber while walking and transfer tensile forces along the bottom of the foot 100.
FIG. 2 illustrates a simplified side view of tissue and bone structure in the human foot 100. As shown in FIG. 2, the human foot 100 includes the plantar fascia 110, a plantar calcaneus 160, a talus 162, a navicular 164, a cuneiform 166, a cuboid 168, metatarsals 170, phalanges 172, a sesamoid 174, a fat pad area 176, and an outer skin surface 178. From the side view in FIG. 2, the plantar calcaneus 160, the talus 162, the navicular 164, the cuneiform 166, the cuboid 168, the metatarsals 170, and the sesamoid 174 form what resembles the shape of an arch. This shape is commonly referred to as the longitudinal arch. Another arch commonly referred to as the transverse arch (metatarsal) also exists in about the same area in a perpendicular direction that runs laterally across the width of the foot.
The plantar fascia 110 serves the vital role of maintaining the shape of the two anatomical arches of the foot, the transverse arch and the longitudinal arch. As illustrated in FIGS. 1 and 2, the plantar fascia 110 runs across the bottom of the foot 100 from the heel 101 to the ball 102 and spreads out across the width of the foot 100. As longitudinal and lateral tensile stresses are produced in the bottom of the foot 100, the plantar fascia 110 absorbs the tensile forces and maintains the shape of the two anatomical arches.
For example, while standing or while in motion, forces experienced by the foot 100 act in a direction which tends to flatten the arches. The stress line 300 in FIG. 2 shows an approximation of the line of forces transferred through foot 100 during typical motion. As shown in FIG. 2, the stress line 300 resembles the shape of an archer's bow. The plantar fascia 110 running along near the bottom surface of the foot 100 is analogous to a string in the archer's bow. Forces that tend to move the ends of the bow apart increase tension on the string. In other words, as forces on the arch push the bones downward, the plantar fascia 110 is subjected to tensile forces.
If the tension on the plantar fascia 110 becomes excessive, the plantar fascia 110 may be damaged and produce a condition called plantar fasciitis. Plantar fasciitis is a painful medical condition resulting from inflammation of the plantar fascia 110. The plantar fascia 110 is thick and essentially inelastic. Overstressing the plantar fascia 110 may produce tears in the plantar fascia 110 or separate the plantar fascia 110 from bone and other surrounding materials. Tearing and separation of the plantar fascia 110 produces the painful inflammation known as plantar fasciitis. Frequently, the inflamed areas 305 are along the arch of the foot 100 or near the heel 101 of the foot 100 as shown in FIG. 2.
Plantar fasciitis may be quite debilitating in that everyday activities such as walking and standing may be very painful. Typical treatments for plantar fasciitis may involve oral anti-inflammatories, ice packs, bedrest, stretching, steroid injections, night splints and wedge-shaped arch supports. In extreme cases, treatment of plantar fasciitis may require corrective surgery.
For example, a design for an orthotic device for treatment of plantar fasciitis is disclosed in Gleason, U.S. Pat. No. 5,865,779. The device of Gleason is an elastic sock that is worn on a patient's foot. The elastic sock exerts compressive forces along the longitudinal and transverse axes of the patient's foot.
While some patients may be willing to wear an elastic sock, the elastic sock is both inconvenient and cumbersome. In order to be installed on the foot, the elastic sock must be stretched to fit over the heel and toe of the foot. Because the sock is elastic, the sock allows the foot to move and stretch. Consequently, the plantar fascia may still be subjected to excessive tensile forces during the critical heeling process. Re-subjecting the plantar fascia to tensile forces before it has completely healed may re-aggravate damaged portions of the plantar fascia and undermine the healing process.
In addition, the elastic sock is meant to be worn multiple times and may require regular cleaning to avoid odors and foot infections. Also, the sock may not fit inside a shoe while being worn and may be considered unsightly while walking around with bare feet. Consequently, the elastic sock does not prevent excessive stretching of the plantar fascia and is both inconvenient and cumbersome.
Another typical example of treatment for plantar fasciitis includes medical personnel strapping strips of tape to the bottom of an injured foot. Strips of tape are applied at various angles across the bottom of the foot. The tape is difficult to remove from the rolls and bunches up during the taping process. Thus, care must be exercised during the application of the tape to avoid blister-causing wrinkles in the tape and other problems.
As the patient walks with the taped foot, the tape works loose and stretches with time. In addition, the tape cannot be effectively applied by the patient to the patient's own foot and requires application by another individual such as a trained medical technician. Consequently, taping the foot is cumbersome, inefficient, and ineffective in preventing excessive stretching of the plantar fascia.
Sometimes when current methods of treatment for plantar fasciitis are ineffective, expensive surgical procedures are required to relieve the pain of plantar fasciitis. To get at the plantar fascia, surgeons may perform either an endoscopic procedure requiring small incisions or conventional direct visualization requiring the underside of the foot to be opened up. With either painful procedure, scars may result and recovery time may be from weeks to months.
Even with treatment, improper treatment of plantar fasciitis may lead to other medical problems. For example, if inflammation near the heel is allowed to continue for a long period of time, calcium deposits may build-up in the damaged region. As the calcium builds-up, bony outcroppings may develop in the heel that are commonly referred to as “heel spurs”. The longer the plantar fascia remains inflamed around the heel, the stronger the conditions are for the development of heel spurs. Protrusion of the heel spurs into the surrounding tissue may result in a cycle of irritation, inflammation, and pain known as heel spur syndrome.
Heel spur syndrome is commonly treated with a surgical procedure requiring removal of the heel spurs from within the foot. An endoscopic procedure is typically not used for removal of heel spurs and open surgery is typically required. Recovery time from such surgery may range from weeks to months, during which time the patient has to curtail the amount of stress placed on the foot.
Thus, it may be highly desirable to have a system for avoiding and/or treating the pain of plantar fasciitis. It may also be highly desirable to have a system for treating plantar fasciitis that is economical and may be easily applied by the patient. It may also be highly desirable to have a system for treating plantar fasciitis that is discretely attached to the sole of the patient's foot and includes a substantially stretch resistant material to reduce tensile forces in the plantar fascia.